The Rocky Mountain National Park Act was signed by President Woodrow Wilson on January 26, 1915, establishing the park boundaries and protecting the area for future generations.[2] The Civilian Conservation Corps built the main automobile route, Trail Ridge Road, in the 1930s.[2] In 1976, UNESCO designated the park as one of the first World Biosphere Reserves.[6] In 2017, more than 4.4 million recreational visitors entered the park.[7] The park is one of the most visited in the National Park System, ranking as the third most visited national park in 2015.[8]

Rocky Mountain National Park encompasses 265,461 acres (414.78 sq mi; 1,074.28 km2) of federal land,[1] with an additional 253,059 acres (395.40 sq mi; 1,024.09 km2) of U.S. Forest Service wilderness adjoining the park boundaries.[24] The Continental Divide runs generally north–south through the center of the park,[25] with rivers and streams on the western side of the divide flowing toward the Pacific Ocean while those on the eastern side flow toward the Atlantic.[26]

A geographical anomaly is found along the slopes of the Never Summer Mountains where the Continental Divide forms a horseshoe–shaped bend for about 6 miles (9.7 km), heading from south–to–north but then curving sharply southward and westward out of the park.[5][27] The sharp bend results in streams on the eastern slopes of the range joining the headwaters of the Colorado River that flow south and west, eventually reaching the Pacific.[5][28] Meanwhile, streams on the western slopes join rivers that flow north and then east and south, eventually reaching the Atlantic.[5][28]

View from Many Parks Curve on Trail Ridge Road. The "parks" in the Rockies are meadows that formed when glacial lakes drained.

The headwaters of the Colorado River are located in the park's northwestern region.[25] The park contains approximately 450 miles (724 km) of rivers and streams, 350 miles (563 km) of trails, and 150 lakes.[25][29]

Region 1 is known for moose and big meadows and is located on the west, or Grand Lake, side of the Continental Divide.[35] Thirty miles of the Continental Divide National Scenic Trail loop through the park and pass through alpine tundra and scenery.[36]

Bull elk in a meadow near the headwaters of the Colorado River

The Big Meadows area with its grasses and wildflowers can be reached via the Onahu, Tonahutu, or Green Mountain trail. Other scenic areas include Long Meadows and the Kawuneeche Valley (Coyote Valley) of the upper Colorado River which is a good place for birdwatching, as well as snowshoeing and cross-country skiing in winter. The valley trail loops through Kawuneeche Valley[36] which contained as many as 39 mines, though less than 20 of those have archived records and archeological remains.[37]LuLu City is the site of an abandoned silver mining town of the early 1880s located along the Colorado River Trail.[5] According to a 1985 report prepared for the NRHP, there were only three cabin ruins remaining along with remnants of six other buildings.[38]

Baker Pass crosses the Continental Divide through the Never Summer Mountains and into the Michigan River drainage to the west of Mount Nimbus[36]—a drainage that feeds streams and rivers that drain into the Gulf of Mexico.[28] Other mountain passes are La Poudre Pass and Thunder Pass, which was once used by stage coaches and is a route to Michigan Lakes. Little Yellowstone has unique geological features similar to the Grand Canyon of the Yellowstone. The Green Mountain trail once was a wagon road used to haul hay from Big Meadows. Flattop Mountain, which can be accessed from the eastern and western sides of the park, is near Green Mountain. Shadow Mountain Lookout—a wildfire observation tower—is on the National Register of Historic Places.[36] Paradise Park is an essentially hidden and protected wild area with no maintained trails penetrating it.[39]

Skeleton Gulch, Cascade Falls, North Inlet Falls, Granite Falls, and Adams Falls are found in the west side of the park. The west side lakes include Bowen Lake, Lake Verna, Lake of the Clouds, Haynach Lakes, Timber Lake, Lone Pine Lake, Lake Nanita, and Lake Nokoni.[36]

Region 2 is the alpine region of the park with accessible tundra trails at high elevations—an area known for its spectacular vistas.[35] Within the region are Mount Ida, with tundra slopes and a wide-open view of the Continental Divide, and Specimen Mountain, which has a steep trail and the opportunity to view bighorn sheep and marmots. Forest Canyon Pass is near the top of the Old Ute Trail that once linked villages across the Continental Divide.[40]

Chapin Pass trail traverses a dense forest to beautiful views of the Chapin Creek valley, proceeding onward above timberline to the western flank of Mount Chapin. Tundra Communities Trail, accessible from Trail Ridge Road, is a hike offering tundra views and alpine wildflowers. Other trails are Tombstone Ridge and Ute Trail, which starts at the tundra and is mostly downhill from Ute Crossing to Upper Beaver Meadows, with one backcountry camping site. Cache La Poudre River trail begins north of Poudre Lake on the west side of the valley near Milner Pass and heads downward toward the Mummy Pass trail junction. Lake Irene is a recreation and picnic area.[40]

The alpine tundra of Rocky Mountain National Park taken along the Tundra Communities Trail at approximately 12,000 feet. Longs Peak (14,259') is located in the distance near the center of the panorama.

The Mummy Range is a short mountain range in the north of the park. The Mummies tend to be gentler and more forested than the other peaks in the park, though some slopes are rugged and heavily glaciated, particularly around Ypsilon Mountain and Mummy Mountain. Bridal Veil Falls is a scenic point and trail accessible from the Cow Creek trailhead, at the Continental Divide Research Center.[41] West Creek Falls and Chasm Falls, near Old Fall River Road, are also in this region. The Alluvial Fan trail leads to a bridge over the river that had been the site of the Lawn Lake Flood.[42]

Lumpy Ridge Trail leads to Paul Bunyan's Boot at about 1.5 mi (2.4 km) from the trailhead, then Gem Lake, and a further 2.2 mi (3.5 km) to Balanced Rock.[43] Black Canyon Trail intersects Cow Creek Trail, forming part of the Gem Lake loop which goes through the old McGregor Ranch valley, passing Lumpy Ridge rock formations, with a loop hike that goes into the McGraw Ranch valley.[42]

Cow Creek Trail follows Cow Creek, with its many beaver ponds, extending past the Bridal Falls turnoff as the Dark Mountain trail, then joining the Black Canyon trail to intersect the Lawn Lake trail shortly below the lake.[42] North Boundary Trail connects to the Lost Lake trail system. North Fork Trail begins outside of the park in the Comanche Peak Wilderness before reaching the park boundary and ending at Lost Lake. Stormy Peaks Trail connects Colorado State University's Pingree Park campus in the Comanche Peak Wilderness and the North Fork Trail inside the park.[42]

Beaver Mountain Loop, also used by horseback riders, passes through forests and meadows, crosses Beaver Brook and several aspen-filled drainages, and has a great view of Longs Peak.[42] Deer Mountain Trail gives a 360 degree view of eastern part of the park. The summit plateau of Deer Mountain offers expansive views of the Continental Divide. During the winter, the lower trail generally has little snow, though packed and drifted snow are to be expected on the switchbacks. Snow cover on the summit may be three to five feet deep, requiring the use of snowshoes or skis.[42]

The trail to Lake Estes in Estes Park meanders through a bird sanctuary, beside a golf course, along the Big Thompson River and Fish Creek, through the lakeside picnic area and along the lakeshore. The trail is used by birdwatchers, bikers and hikers.[42]

Lawn Lake Trail climbs to Lawn Lake and Crystal Lake, one of the parks deepest lakes, in the alpine ecosystem and along the course of the Roaring River. The river shows the massive damage caused by a dam failure in 1982 that claimed the lives of three campers. The trail is a strenuous snowshoe hike in the winter.[42] Ypsilon Lake Trail leads to its namesake as well as Chipmunk Lake, with views of Longs Peak, while traversing pine forests with grouseberry and bearberry bushes. The trail also offers views of the canyon gouged out by rampaging water that broke loose from Lawn Lake Dam in 1982. Visible is the south face of Ypsilon Mountain, with its Y shaped gash rising sharply from the shoreline.[42]

Gem Lake is high among the rounded granite domes of Lumpy Ridge. Untouched by glaciation, this outcrop of 1.8 billion-year-old granite has been sculpted by wind and chemical erosion into a backbone-like ridge. Pillars, potholes, and balanced rocks are found around the midpoint of the trail, along with views of the Estes Valley and Continental Divide.[42] Potts Puddle trail is accessible from the Black Canyon trail.[42]

Region 4 is the heart of the park with easy road and trail access, great views, and lake hikes including the most popular trails.[35] Flattop Mountain is a tundra hike and the easiest hike to the Continental Divide in the park. Crossing over Flattop Mountain, the hike to Hallett Peak passes through three climate zones, traversing the ridge that supports Tyndall Glacier and finally ascending to the summit of Hallett Peak.[44]

Bear Lake is a high-elevation lake in a spruce and fir forest at the base of Hallett Peak and Flattop Mountain.[44]Bierstadt Lake sits atop a lateral moraine named Bierstadt Moraine, and drains into Mill Creek. There are several trails that lead to Bierstadt Lake through groves of aspens and lodgepole pines.[45] North of Bierstadt Moraine is Hollowell Park, a large and marshy meadow along Mill Creek. The Hollowell Park trail runs along Steep Mountain's south side. Ranches, lumber and sawmill enterprises operated in Hollowell Park into the early 1900s.[45]

Glacial Basin was the site of a resort run by Abner and Alberta Sprague, after whom Sprague Lake is named. The lake is a shallow body of water that was created when the Spragues dammed Boulder Brook to create a fish pond. Sprague Lake is a popular place for birdwatching, hiking and viewing the mountain peaks, along with camping at the Glacier Basin campground.[46]

Emerald Lake and Hallett Peak

Dream Lake is one of the most-photographed lakes and is also noted for its winter snowshoeing. Emerald Lake is located directly below the saddle between Hallett Peak and Flattop Mountain, only a short hike beyond Dream Lake.[44] The shore of Lake Haiyaha (a Native American word for "big rocks") is surrounded by boulders along with ancient, twisted and picturesque pine trees growing out of rock crevices. Nymph Lake is named for the yellow lily, Nymphaea polysepala, on its surface. Lake Helene is at the head of Odessa Gorge, east of Notchtop Mountain. Two Rivers Lake is found along the hike to Odessa Lake from Bear Lake, and has one backcountry campsite. The Cub Lake trail passes Big Thompson River, flowery meadows, and stands of pine and aspen trees. Ice and deep snow are present during the winter, requiring the use of skis or snowshoes.[44]

The Fern Lake trail passes Arch Rock formations, The Pool, and the cascading water of Fern Falls. Two backcountry campsites are located near the lake, and two more are closer to the trailhead. Odessa Lake has two approaches: one is along the Flattop trail from Bear Lake while the other is from the Fern Lake trailhead, along which are Fern Creek, The Pool, Fern Falls, and Fern Lake itself. One backcountry campsite is available.[44] Other lakes are Jewel Lake, Mills Lake, Black Lake, Blue Lake, Lake of Glass, and Spruce Lake.[44]

View from the summit of Hallett Peak

The Pool is a large turbulent water pocket formed below where Spruce and Fern Creeks join the Big Thompson River. The winter route is along a gravel road, which leads to a trail at the Fern Lake trailhead. Along the route are beaver-cut aspen, frozen waterfalls on the cliffs, and the Arch Rocks.[44] The trail to Alberta Falls runs by Glacier Creek and Glacier Gorge.[44]

Wind River Trail leaves the East Portal and follows the Wind River to join with the Storm Pass trail. There are three backcountry campsites.[44] Other sites in the area are The Loch, Loch Vale, Mill Creek Basin, Andrews Glacier, Sky Point, Timberline Falls, Upper Beaver Meadows, and Storm Pass.[44]

Region 5, known for waterfalls and backcountry, is south of Estes Park and contains Longs Peak—the park's iconic fourteener—and the Wild Basin area.[35] Other peaks and passes include Lily Mountain, Estes Cone, Twin Sisters, Boulder-Grand Pass, and Granite Pass.[47] Eugenia Mine operated about the late-19th to early-20th century, with some old equipment and a log cabin remaining.[47] Sites and trails include Boulder Field, Wild Basin Trail, and Homer Rouse Memorial Trail.[47]

Enos Mills, the main figure behind the creation of Rocky Mountain National Park, enjoyed walking to Lily Lake from his nearby cabin. Wildflowers are common in the spring and early summer. In the winter, the trail around the lake is often suitable for walking in boots, or as a short snowshoe or ski. Other lakes in the Wild Basin include Chasm Lake, Snowbank Lake, Lion Lakes 1 and 2, Thunder Lake, Ouzel Lake, Finch Lake, Bluebird Lake, Pear Lake, and Sandbeach Lake. Many of the lakes have backcountry campsites. Waterfalls include Ouzel Falls, Trio Falls, Copeland Falls, and Calypso Cascades.[47]

The complex interactions of elevation, slope, exposure and regional-scale air masses determine the climate within the park,[48][49] which is noted for its extreme weather patterns.[49] A "collision of air masses" from several directions produces some of the key weather events in the region. When cold arctic air from the north meets warm moist air from the Gulf of Mexico at the Front Range, "intense, very wet snowfalls with total snow depth measured in the feet" accumulate in the park.[48]

Higher elevation areas within the park receive twice as much precipitation as lower elevation areas, generally in the form of deep winter snowfall.[48] Arctic conditions are prevalent during the winter, with sudden blizzards, high winds, and deep snowpack. High country overnight trips require gear suitable for -35 °F or below.[49]

The subalpine region does not begin to experience spring-like conditions until June. Wildflowers bloom from late June to early August.[49]

Below 9,400 feet (2,865 m), temperatures are often moderate, although nighttime temperatures are cool, as is typical of mountain weather.[49] Spring comes to the montane area by early May, when wildflowers begin to bloom. Spring weather is subject to unpredictable changes in temperature and precipitation, with potential for snow along trails through May.[49] In July and August, temperatures are generally in the 70s or 80s °F during the day, and as low as the 40s °F at night.[49] Lower elevations receive rain as most of their summer precipitation.[48]

Sudden dramatic changes in the weather may occur during the summer, typically due to afternoon thunderstorms that can cause as much as a 20 °F drop in temperature and windy conditions.[49]

The park's climate is also affected by the Continental Divide, which runs northwest to southeast through the center of the park atop the high peaks. The Continental Divide creates two distinct climate patterns - one typical of the east side near Estes Park and the other associated with the Grand Lake area on the park's west side.[49] The west side of the park experiences more snow, less wind, and clear cold days during the winter months.[49]

Rocky Mountain National Park was selected to participate in a climate change study, along with two other National Park Service areas in the Rocky Mountain region and three in the Appalachian Mountain region.[50] The study began in 2011, orchestrated by members of the academic scientific community in cooperation with the National Park Service and the National Aeronautics and Space Administration (NASA).[50] The stated objective: "develop and apply decision support tools that use NASA and other data and models to assess vulnerability of ecosystems and species to climate and land use change and evaluate management options."[51]

As of 2010[update], the preceding one hundred years of records indicated an increase in the average annual temperature of approximately 3 °F (1.7 °C).[48][52][a] The average low temperature has increased more than the average high temperature during the same time period.[48] As a result of the temperature increase, snow is melting from the mountains earlier in the year, leading to drier summers and probably to an earlier, longer fire season.[48] Since the 1990s, mountain pine beetles have reproduced more rapidly and have not died off at their previous mortality rate during the winter months. Consequently, the increased beetle population has led to an increased rate of tree mortality in the park.[53]

The climate change study projects further temperature increases, with greater warming in the summer and higher extreme temperatures by 2050. Due to the increased temperature, there is a projected moderate increase in the rate of water evaporation. Reduced snowfall—perhaps 15% to 30% less than current amounts—and the elimination of surface hail, along with the higher likelihood of intense precipitation events are predicted by 2050. Droughts may be more likely due to increased temperatures, increased evaporation rates, and potential changes in precipitation.[53]

Precambrianmetamorphic rock formed the core of the North American continent during the Precambrian eon 4.5–1 billion years ago. During the Paleozoic era, western North America was submerged beneath a shallow sea, with a seabed composed of limestone and dolomite deposits many kilometers thick.[54]Pikes Peak granite formed during the late Precambrian eon, continuing well into the Paleozoic era, when mass quantities of molten rock flowed, amalgamated, and formed the continents about 1 billion–300 million years ago. Concurrently, in the period from 500–300 million years ago, the region began to sink while lime and mud sediments were deposited in the vacated space. Eroded granite produced sand particles that formed strata—layers of sediment—in the sinking basin.[55]

About 300 million years ago, the land was uplifted creating the ancestral Rocky Mountains.[55]Fountain Formation was deposited during the Pennsylvanian period of the Paleozoic era, 290–296 million years ago. Over the next 150 million years, the mountains uplifted, continued to erode, and covered themselves in their own sediment. Wind, gravity, rainwater, snow, and glacial ice eroded the granite mountains over geologic time scales.[56] The Ancestral Rockies were eventually buried under subsequent strata.[57]

Cretaceous seaway

The Pierre Shale formation was deposited during the Paleogene and Cretaceous periods about 70 million years ago. The region was covered by a deep sea—the Cretaceous Western Interior Seaway—which deposited massive amounts of shale on the seabed. Both the thick stratum of shale and embedded marine life fossils—including ammonites and skeletons of fish and such marine reptiles as mosasaurs, plesiosaurs, and extinct species of sea turtles, along with rare dinosaur and bird remains—were created during this time period. The area now known as Colorado was eventually transformed from being at the bottom of an ocean to dry land again, giving yield to another fossiliferous rock layer known as the Denver Formation.[58]

At about 68 million years ago, the Front Range began to rise again due to the Laramide orogeny in the west.[58][59] During the Cenozoic era, block uplift formed the present Rocky Mountains. The geologic composition of Rocky Mountain National Park was also affected by deformation and erosion during that era. The uplift disrupted the older drainage patterns and created the present drainage patterns.[60]

Glacial geology in Rocky Mountain National Park can be seen from the mountain peaks to the valley floors. Ice is a powerful sculptor of this natural environment and large masses of moving ice are the most powerful tools. Telltale marks of giant glaciers can be seen all throughout the park. Streams and glaciations during the Quaternary period cut through the older sediment, creating mesa tops and alluvial plains, and revealing the present Rocky Mountains.[61] The glaciation removed as much as 5,000 feet (1,500 m) of sedimentary rocks from earlier inland sea deposits. This erosion exposed the basement rock of the Ancestral Rockies. Evidence of the uplifting and erosion can be found on the way to Rocky Mountain National Park in the hogbacks of the Front Range foothills.[60] Many sedimentary rocks from the Paleozoic and Mesozoic eras exist in the basins surrounding the park.[62]

Colorado has one of the most diverse plant and animal environments of the United States, partially due to the dramatic temperature differences arising from varying elevation levels and topography. In dry climates, the average temperature drops 5.4 degrees Fahrenheit with every 1,000 foot increase in elevation (9.8 degrees Celsius per 1,000 meters). Most of Colorado is semi-arid with the mountains receiving the greatest amount of precipitation in the state.[64]

The Continental Divide runs north to south through the park, creating a climatic division. Ancient glaciers carved the topography into a range of ecological zones.[30] The east side of the Divide tends to be drier with heavily glaciated peaks and cirques. The west side of the park is wetter with more lush, deep forests.[65]

There are four ecosystems, or zones, in Rocky Mountain National Park: montane, subalpine, alpine tundra, and riparian. The riparian zone occurs throughout all of the three other zones. Each individual ecosystem is composed of organisms interacting with one other and with their surrounding environment. Living organisms (biotic), along with the dead organic matter they produce, and the abiotic (non-living) environment that impacts those living organisms (water, weather, rocks, and landscape) are all members of an ecosystem.[66]

From 9,000 ft (2,700 m) to 11,000 ft (3,400 m),[72] the montane forests give way to subalpine forests.[69] Forests of fir and Engelmann spruce cover the mountainsides in subalpine areas. Trees grow straight and tall in the lower subalpine forests, but become shorter and more deformed the nearer they are to the tree line.[72] At the tree line, seedlings may germinate on the lee side of rocks and grow only as high as the rock provides wind protection, with any further growth being more horizontal than vertical. The low growth of dense trees is called krummholz, which may become well-established and live for several hundred to a thousand years old.[72]

Above tree line, at approximately 11,000 ft (3,400 m), trees disappear and the vast alpine tundra takes over.[69] Over one third of the park resides above the tree line, an area which limits plant growth due to the cold climate and strong winds. The few plants that can survive under such extreme conditions are mostly perennials. Many alpine plants are dwarfed at high elevations, though their occasional blossoms may be full-sized.[73]

View on Tundra Communities Trail

Cushion plants have long taproots that extend deep into the rocky soil. Their diminutive size, like clumps of moss, limits the effect of harsh winds. Many flowering plants of the tundra have dense hairs on stems and leaves to provide wind protection or red-colored pigments capable of converting the sun's light rays into heat. Some plants take two or more years to form flower buds, which survive the winter below the surface and then open and produce fruit with seeds in the few weeks of summer. Grasses and sedges are common where tundra soil is well-developed.[73]

Mountain stream along Fall River Road is an example of a riparian ecosystem.

The riparian ecosystem runs through the montane, subalpine, and alpine tundra zones and creates a foundation for life, especially for species that thrive next to streams, rivers, and lakes.[74] The headwaters of the Colorado River, which provides water to many of the southwestern states, are located on the west side of the park. The Fall River, Cache la Poudre River and Big Thompson Rivers are located on the east side of the park. Just like the other ecosystems in the park, the riparian zone is affected by the climatic variables of temperature, precipitation, and elevation. Generally, riparian zones in valleys will have cooler temperatures than communities located on slopes and ridge tops. Depending on elevation, a riparian zone may have more or less precipitation than other riparian zones in the park, with the difference creating a shift in the types of plants and animals found in a specific zone.[75]

Rocky Mountain National Park is home to many species of animals, including nearly 70 mammals and almost 300 species of birds. This diversity is due to the park's varying topography, which creates a variety of habitats. However, some species have been extirpated from the park, including the gray wolf, the wolverine, the grizzly bear, and the American bison.

The park is home to some 2,000 to 3,000 elk in summer, and between 800 and 1,000 elk spend the winter within its boundaries. Because of lack of predation, the National Park Service culls around 50 elk each winter. Overgrazing by elk has become a major problem in the park's riparian areas, so much so that the NPS fences them out of many critical wetland habitats to let willows and aspens grow. The program seems to be working, as the deciduous wetland plants thrive within the fencing. Many people think the elk herd is too large, but are reluctant to reintroduce predators because of its proximity to large human populations and ranches.[76]

Apart from elk, many other ungulates reside in the park, including bighorn sheep, moose, and mule deer. Bison were eliminated from the park in the 1800s, as were pronghorn and moose, the latter of which was restored to the area in 1978. Moose are now frequently seen in the park, especially on the park's west side.[77] The park's bighorn sheep population has recovered and is estimated at 350 animals.[78]

The park is home to many predatory animals, including Canadian lynx, foxes, bobcat, cougar, black bear, and coyotes. Wolves and grizzly bears were extirpated in the early 1900s. Most of these predators kill smaller animals, but mountain lions and coyotes kill deer and occasionally elk. Bears also eat larger prey. Moose have no predators in the park. Black bears are relatively uncommon in the park, numbering only 24-35 animals. They also have fewer cubs and the bears seem skinnier than they do in most areas.[79] Canadian lynx are quite rare within the park, and they have probably spread north from the San Juan Mountains, where they were reintroduced in 1999. Cougars feed mainly on mule deer in the park, and live 10–13 years. Cougar territories can be as large as 500 square miles.[80] Coyotes hunt both alone and in pairs, but occasionally hunt in packs. They mainly feed on rodents but occasionally bring down larger animals, including deer, and especially fawns and elk calves. Scat studies in Moraine Park showed that their primary foods were deer and rodents. They form strong family bonds and are very vocal.[81]

The park contains a network of trails that range from easy, paved paths suitable for all visitors including those with disabilities, to strenuous mountain trails for experienced, conditioned hikers as well as off-trail routes for backcountry hikes. Most trails are for summer use only, since at other times of the year many trails are not safe due to weather conditions.[82] The park provides dozens of designated backcountry campsites and horseback riding is permitted on most trails.[83] Llamas and other pack animals are also allowed on most of the trails.[84]

Rock climbing and mountaineering opportunities include Lumpy Ridge,[85]Hallett Peak, and Longs Peak, the highest peak in the park, with the easiest route being the Keyhole Route. This 8 mi (13 km) one-way climb has an elevation gain of 4,850 ft (1,480 m). The vast east face, including the area known as The Diamond, is home to many classic big wall rock climbing routes. Many of the highest peaks have technical ice and rock routes on them, ranging from short scrambles to long multi-pitch climbs.[citation needed]

Fishing is found in the many lakes and streams in the park,[83] and camping is allowed at several designated campgrounds.[86]

During the winter, only the edges of the park are accessible for recreational activities since most of Trail Ridge Road is closed due to heavy snow.[68] Winter activities include snowshoeing and cross-country skiing which are possible from either the Estes Park or Grand Lake entrances. On the east side near Estes Park, skiing and snowshoeing trails are available off Bear Lake Road, such as the Bear Lake, Bierstadt Lake, and Sprague Lake trails and at Hidden Valley. Slopes for sledding are also available at Hidden Valley. The west side of the park near Grand Lake also has viable snowshoeing trails.[68][87] Backcountry-style Telemark skiing and snowboarding can be enjoyed after climbing up one of the higher slopes, late in the snow season after avalanche danger has subsided.[88]

Trail Ridge Road is the highest continuously paved highway in the United States.

The park may be accessed through Estes Park or via the western entrance at Grand Lake. Trail Ridge Road, also known as U.S. Route 34, connects the eastern and western sides of the park.[89] The park has a total of five visitor centers. The Alpine Visitor Center is located in the tundra environment along Trail Ridge Road, while Beaver Meadows and Fall River are both near Estes Park, with Kawuneeche in the Grand Lake area, and the Moraine Park Discovery Center near the Beaver Meadows entrance and visitor center.[9]

Trail Ridge Road is 48 miles (77 km) long and connects the entrances in Grand Lake and Estes Park.[90][91] Running generally east–west through many hairpin turns,[5] the road crosses Milner Pass through the Continental Divide[91] at an elevation of 10,758 ft (3,279 m).[90][92] The highest point of the road is 12,183 feet (3,713 m),[91] with eleven miles of the road being above tree line which is approximately 11,500 feet (3,505 m).[90] The road is the highest continuously paved highway in the country,[91] and includes many large turnouts at key points to stop and observe the scenery.[90]

Schematic map of Trail Ridge Road's northern sections

Most visitors to the park drive over the famous Trail Ridge Road, but other roads include Fall River Road and Bear Lake Road.[93] The park is open every day of the year, weather permitting.[94] Due to the extended winter season in higher elevations, Trail Ridge Road between Many Parks Curve and the Colorado River Trailhead is closed much of the year. The road is usually open again by Memorial Day and closes in mid-October, generally after Columbus Day.[91] Fall River Road does not open until about July 4 and closes by, or in, October for vehicular traffic.[95] Snow may also fall in sufficient quantities in higher elevations to require temporary closure of the roads into July,[49][91] which is reported on the road status site.[93]

Most visitors enter the park through the eastern entrances near Estes Park, which is about 71 miles (114 km) northwest of Denver.[89] The most direct route to Trail Ridge Road is the Beaver Meadows entrance, located just west of Estes Park on U.S. Route 36, which leads to the Beaver Meadows Visitor Center and the park's headquarters. North of the Beaver Meadows entrance station is the Fall River entrance, which also leads to Trail Ridge Road and Old Fall River Road.[89] There are three routes into Estes Park: I-25 to U.S. 34 west which runs alongside the Big Thompson River; U.S. 36 west (northwest) from Boulder connecting to U.S. 34 west; and the Peak to Peak Highway, also known as State Highway 7, from points south.[89]

The nearest airport is Denver International Airport[89] and the closest train station is the Denver Union Station. Estes Park may be reached by rental car, shuttle or RTD bus.[89][96] During peak tourist season, there is free shuttle service within the park and the town of Estes Park provides shuttle service to Estes Park Visitor Center, surrounding campgrounds, and the Rocky Mountain National Park's shuttles.[89]

Visitors may also enter at the western side of the park from U.S. 34 near Grand Lake. U.S. 34 is reached by taking U.S. 40 north from I-70.[89] The closest railroad station is the Amtrak station in Granby, which is 20 miles (32 km) from the western entrance of the park. Taxi service is available into the park.[96]

^Montana State University states in their profile of Rocky Mountain National Park that there has been an increase of 2.5 °F (1.4 °C) in the average park temperature over "the past century" (charts show the period from about 1895-2010).[48] The National Park Service site states that the increase has been 3.4 °F (1.9 °C) over "the last century" (chart shows the period from about 1905-2010).[52]

1.
International Union for Conservation of Nature
–
The International Union for Conservation of Nature is an international organization working in the field of nature conservation and sustainable use of natural resources. It is involved in gathering and analysis, research, field projects, advocacy, lobbying. IUCNs mission is to influence, encourage and assist societies throughout the world to conserve nature and to ensure that any use of resources is equitable. Over the past decades, IUCN has widened its focus beyond conservation ecology and now incorporates issues related to equality, poverty alleviation. Unlike other international NGOs, IUCN does not itself aim to mobilize the public in support of nature conservation and it tries to influence the actions of governments, business and other stakeholders by providing information and advice, and through lobbying and partnerships. The organization is best known to the public for compiling and publishing the IUCN Red List. IUCN has a membership of over 1200 governmental and non-governmental organizations, some 11,000 scientists and experts participate in the work of IUCN commissions on a voluntary basis. It employs approximately 1000 full-time staff in more than 60 countries and its headquarters are in Gland, Switzerland. IUCN has observer and consultative status at the United Nations, and plays a role in the implementation of several conventions on nature conservation. It was involved in establishing the World Wide Fund for Nature, in the past, IUCN has been criticized for placing the interests of nature over those of indigenous peoples. In recent years, its relations with the business sector have caused controversy. It was previously called the International Union for Protection of Nature, establishment In 1947, the Swiss League for the Protection of Nature organised an international conference on the protection of nature in Brunnen. It is considered to be the first government-organized non-governmental organization, the initiative to set up the new organisation came from UNESCO and especially from its first Director General, the British biologist Julian Huxley. At the time of its founding IUPN was the international organisation focusing on the entire spectrum of nature conservation Early years. Its secretariat was located in Brussels and its first work program focused on saving species and habitats, increasing and applying knowledge, advancing education, promoting international agreements and promoting conservation. Providing a solid base for conservation action was the heart of all activities. IUPN and UNESCO were closely associated and they jointly organized the 1949 Conference on Protection of Nature. In preparation for this conference a list of endangered species was drawn up for the first time

2.
National park
–
A national park is a park in use for conservation purposes. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state declares or owns, although individual nations designate their own national parks differently, there is a common idea, the conservation of wild nature for posterity and as a symbol of national pride. An international organization, the International Union for Conservation of Nature, although Yellowstone was not officially termed a national park in its establishing law, it was always termed such in practice and is widely held to be the first and oldest national park in the world. The first area to use national park in its legislation was the USs Mackinac Island. Australias Royal National Park, established in 1879, was the third official national park. In 1895 ownership of Mackinac Island was transferred to the State of Michigan as a state park, as a result, Australias Royal National Park is by some considerations the second oldest national park now in existence. The largest national park in the meeting the IUCN definition is the Northeast Greenland National Park. According to the IUCN,6,555 national parks worldwide met its criteria in 2006, IUCN is still discussing the parameters of defining a national park. National parks are almost always open to visitors, in 1971, these criteria were further expanded upon leading to more clear and defined benchmarks to evaluate a national park. In 1810, the English poet William Wordsworth described the Lake District as a sort of property, in which every man has a right and interest who has an eye to perceive. It was known as Hot Springs Reservation, but no authority was established. Federal control of the area was not clearly established until 1877, John Muir is today referred to as the Father of the National Parks due to his work in Yosemite. He published two articles in The Century Magazine, which formed the base for the subsequent legislation. President Abraham Lincoln signed an Act of Congress on July 1,1864, ceding the Yosemite Valley, according to this bill, private ownership of the land in this area was no longer possible. The state of California was designated to manage the park for use, resort. Leases were permitted for up to ten years and the proceeds were to be used for conservation, a public discussion followed this first legislation of its kind and there was a heated debate over whether the government had the right to create parks. The perceived mismanagement of Yosemite by the Californian state was the reason why Yellowstone at its establishment six years later was put under national control, in 1872, Yellowstone National Park was established as the United States first national park, being also the worlds first national park. In some European countries, however, national protection and nature reserves already existed, such as Drachenfels, Yellowstone was part of a federally governed territory

3.
Colorado
–
Colorado is a state in the United States encompassing most of the Southern Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains. Colorado is part of the Western United States, the Southwestern United States, Colorado is the 8th most extensive and the 21st most populous of the 50 United States. The United States Census Bureau estimates that the population of Colorado was 5,540,545 on July 1,2016, the state was named for the Colorado River, which Spanish travelers named the Río Colorado for the ruddy silt the river carried from the mountains. The Territory of Colorado was organized on February 28,1861, Colorado is nicknamed the Centennial State because it became a state in the same year as the centennial of the United States Declaration of Independence. Colorado is noted for its landscape of mountains, forests, high plains, mesas, canyons, plateaus, rivers. Denver is the capital and the most populous city of Colorado, residents of the state are properly known as Coloradans, although the term Coloradoan has been used archaically and lives on in the title of Fort Collins newspaper, the Coloradoan. Colorado, Wyoming and Utah are the states which have boundaries defined solely by lines of latitude and longitude. The summit of Mount Elbert at 14,440 feet elevation in Lake County is the highest point in Colorado, Colorado is the only U. S. state that lies entirely above 1,000 meters elevation. The point where the Arikaree River flows out of Yuma County, Colorado and this point, which holds the distinction of being the highest low elevation point of any state, is higher than the high elevation points of 18 states and the District of Columbia. A little less than one half of the area of Colorado is flat, East of the Rocky Mountains are the Colorado Eastern Plains of the High Plains, the section of the Great Plains within Nebraska at elevations ranging from roughly 3,350 to 7,500 feet. The Colorado plains were mostly prairies, but they have many patches of forests, buttes. Eastern Colorado is presently covered in farmland and rangeland, along with small farming villages. Precipitation is fair, averaging from 15 to 25 inches annually, corn, wheat, hay, soybeans, and oats are all typical crops, and most of the villages and towns in this region boast both a water tower and a grain elevator. Irrigation water is available from the South Platte, the Arkansas River, and a few other streams, however, heavy use of ground water from wells for irrigation has caused underground water reserves to decline. As well as agriculture, eastern Colorado hosts considerable livestock, such as cattle ranches. Roughly 70% of Colorados population resides along the edge of the Rocky Mountains in the Front Range Urban Corridor between Cheyenne, Wyoming, and Pueblo, Colorado. This region is protected from prevailing storms that blow in from the Pacific Ocean region by the high Rockies in the middle of Colorado. The Front Range includes Denver, Boulder, Fort Collins, Loveland, Colorado Springs, Pueblo, Greeley and other townships, on the other side of the Rockies, the significant population centers in Western Colorado are the cities of Grand Junction, Durango, and Montrose

4.
Estes Park, Colorado
–
The Town of Estes Park /ˈɛstɪs/ is a statutory town in Larimer County, Colorado, United States. A popular summer resort and the location of the headquarters for Rocky Mountain National Park, Estes Park had a population of 5,858 at the 2010 census. The town overlooks Lake Estes and Olympus Dam, before Europeans came to the Estes Park valley, the Arapaho Indians lived there in the summertime and called the valley the Circle. When three elderly Arapahoes visited Estes Park in 1914, they pointed out sites they remembered from their younger days, toll, recorder, and David Robert Hawkins, a Princeton student. In the 1850s, the Arapaho had spent summers camped around Marys Lake, where their rock fireplaces, tipi sites and they also recalled building eagle traps atop Longs Peak to get the war feathers coveted by all tribes. They remembered their routes to and from the valley in detail, naming trails and they pointed out the site of their buffalo trap, and described the use of dogs to pack meat out of the valley. Their recollections included a battle with Apaches in the 1850s, and fights with Utes who came to the area to hunt bighorn sheep, whites probably came into the Estes Park valley before the 1850s as trappers, but did not stay long. The town is named after Missouri native Joel Estes, who founded the community in 1859, Estes moved his family there in 1863. One of Estes early visitors was William Byers, an editor who wrote of his ascent of Longs Peak in 1864. Griff Evans and his came to Estes Park in 1867 to act as caretakers for the former Estes ranch. Recognizing the potential for tourism, he began building cabins to accommodate travelers, soon it was known as the first dude ranch in Estes Park, with guides for hunting, fishing, and mountaineering. Lord Dunravens land grab didnt work, but he controlled 6,000 acres before he changed tactics and opened the areas first resort, the Estes Park Hotel, in 1873, Englishwoman Isabella Bird, the daughter of an Anglican minister, came to the United States. Landing at San Francisco, she came overland to Colorado, where she borrowed a horse and set out to explore the Rocky Mountains with a guide, the notorious James Nugent, aka Rocky Mountain Jim. She wrote a memoir of their travels, including the ascent of Longs Peak. On June 19th 1874 Rocky Mountain Jim and neighbor Griff Evans had an argument, having had bitter history with each other, Nugent and Evans hated each other and were deep personal rivals when it came to tour guiding tourists. The argument escalated until Evans blasted Jim in the head with his rifle shotgun, Evans then traveled to Fort Collins to file an assault charge against Nugent, but he was arrested and tried for first degree murder when Jim Nugent died on September 9th 1874 of the bullet wound. Evans was put on trial, but the case was dismissed due to the lack of witnesses to the shooting. On August 9th 1875, the Loveland court-house acquitted Evans of any charges in the case, William Henry Jackson photographed Estes Park in 1873

5.
Grand Lake, Colorado
–
Grand Lake is a statutory town in Grand County, Colorado, United States. The population was 471 at the 2010 census, established in 1881, Grand Lake sits at an elevation of 8,369 feet and derives its name from the lake on whose shores it is situated, Grand Lake, the largest natural body of water in Colorado. Grand Lake was the Grand County seat of government from 1882-1888 and it was incorporated on June 23,1944. Grand Lake is located in northeastern Grand County at 40°15′2″N 105°49′28″W, U. S. Route 34 runs through the western side of the town, entering Rocky Mountain National Park just north of town and leading 45 miles across the mountains to Estes Park. To the southwest, US34 leads 15 miles to Granby, according to the United States Census Bureau, the town has a total area of 1.0 square mile, all of it land. Due to its elevation, Grand Lake has a climate with a short growing season. Temperatures are chilly at night even through the months. Grand Lake is Colorados largest and deepest natural lake, and is part of the headwaters of the Colorado River, the lake became a component in the Colorado-Big Thompson Project in 1937, when it was recruited as a conduit for C-BT project water. The C-BT project diverts water from the Colorado River Basin east via the Alva B, adams Tunnel under the Continental Divide and Rocky Mountain National Park to the Big Thompson River watershed, thence the South Platte River and ultimately the Mississippi River basin. Grand Lake Yacht Club is a club that hosts sailing races on the lake, and there are also publicly and privately operated marinas, a public boat ramp. As of the census of 2000, there were 447 people,219 households, the population density was 472.5 people per square mile. There were 748 housing units at a density of 790.7 per square mile. The racial makeup of the town was 96. 20% White,0. 67% African American,0. 89% Native American,0. 67% Asian,0. 22% from other races, hispanic or Latino of any race were 2. 68% of the population. 35. 2% of all households were made up of individuals and 5. 5% had someone living alone who was 65 years of age or older, the average household size was 2.02 and the average family size was 2.60. In the town, the population was out with 16. 8% under the age of 18,6. 3% from 18 to 24,29. 3% from 25 to 44,35. 6% from 45 to 64. The median age was 44 years, for every 100 females there were 124.6 males. For every 100 females age 18 and over, there were 122.8 males, the median income for a household in the town was $45,096, and the median income for a family was $55,750. Males had an income of $30,833 versus $26,250 for females

6.
National Park Service
–
It was created on August 25,1916, by Congress through the National Park Service Organic Act and is an agency of the United States Department of the Interior. As of 2014, the NPS employs 21,651 employees who oversee 417 units, the National Park Service celebrated its centennial in 2016. National parks and national monuments in the United States were originally individually managed under the auspices of the Department of the Interior, the movement for an independent agency to oversee these federal lands was spearheaded by business magnate and conservationist Stephen Mather, as well as J. Horace McFarland. With the help of journalist Robert Sterling Yard, Mather ran a publicity campaign for the Department of the Interior and they wrote numerous articles that praised the scenic and historic qualities of the parks and their possibilities for educational, inspirational, and recreational benefits. This campaign resulted in the creation of a National Park Service, Mather became the first director of the newly formed NPS. On March 3,1933, President Herbert Hoover signed the Reorganization Act of 1933, the act would allow the President to reorganize the executive branch of the United States government. It wasnt until later that summer when the new President, Franklin D. Roosevelt, President Roosevelt agreed and issued two Executive orders to make it happen. In 1951, Conrad Wirth became director of the National Park Service, the demand for parks after the end of the World War II had left the parks overburdened with demands that could not be met. In 1952, with the support of President Dwight D. Eisenhower, he began Mission 66, New parks were added to preserve unique resources and existing park facilities were upgraded and expanded. In 1966, as the Park Service turned 50 years old, emphasis began to turn from just saving great and wonderful scenery, Director George Hartzog began the process with the creation of the National Lakeshores and then National Recreation Areas. Since its inception in 1916, the National Park Service has managed each of the United States national parks, Yellowstone National Park was the first national park in the United States. In 1872, there was no government to manage it. Yosemite National Park began as a park, the land for the park was donated by the federal government to the state of California in 1864 for perpetual conservation. Yosemite was later returned to federal ownership, at first, each national park was managed independently, with varying degrees of success. In Yellowstone, the staff was replaced by the U. S. Army in 1886. Due to the irregularities in managing these national treasures, Stephen Mather petitioned the government to improve the situation. In response, Secretary of the Interior Franklin K. Lane challenged him to lobby for creating a new agency, Mather was successful with the ratification of the National Park Service Organic Act in 1916. Later, the agency was given authority over other protected areas, the National Park System includes all properties managed by the National Park Service

7.
Denver International Airport
–
Denver International Airport, often referred to as DIA, is an airport in Denver, Colorado, United States. At 33,531 acres, it is the largest airport in the United States by total land area, runway 16R/34L, with a length of 16,000 feet, is the longest public use runway in the United States. As of 2015, DEN was the 18th-busiest airport in the world and it also has the third largest domestic connection network in the country. The airport features 133 gates spread out over three detached, yet connected, linear concourses. DEN has non-stop service to destinations throughout North America, Latin America, Europe, the airport is in northeastern Denver and is operated by the City & County of Denver Department of Aviation. DEN was voted Best Airport in North America by readers of Business Traveler Magazine six years in a row and was named Americas Best Run Airport by Time Magazine in 2002, the airport is the main hub for Frontier Airlines and Great Lakes Airlines. It is also the fourth-largest hub for United Airlines with 375 daily departures to 141 destinations, the airport is Southwest Airlines 4th most utilized airport and fastest-growing market, with 190 daily departures to nearly 60 destinations. DEN is the airport in the United States to have implemented an ISO 14001-certified environmental management system covering the entire airport. The airport is accessible via Peña Boulevard as well as the A Line commuter rail from Denver Union Station, the catenary steel cable system, similar to the Brooklyn Bridge design, supports the fabric roof. Both during construction and after its opening, DIA has set aside a portion of its construction and operation budgets for art, grotesques hiding in suitcases are present above the exit doors from the baggage claims. The corridor from the terminal and Concourse A usually contains additional temporary exhibits. Finally a number of different public art works are present in the train that links the main terminal with the concourses. Blue Mustang, by El Paso born artist Luis Jiménez, was one of the earliest public art commissions for Denver International Airport in 1993. The 32 feet tall Blue Mustang is a bright blue cast-fiberglass sculpture with glowing red eyes located between the inbound and outbound lanes of Peña Boulevard, Jiménez died in 2006 while creating the sculpture when part of it fell on him and severed an artery in his leg. At the time of his death, Jiménez had completed painting the head of the mustang, Blue Mustang was completed by others, and unveiled at the airport on February 11,2008. The statue has been the subject of considerable controversy, other DIA Art Commissions have been awarded to artists Leo Tanguma, Gary Sweeney, and Gary Yazzie. DIAs Art Collection was recently honored by the publishers of USA TODAY, the airport also features a bronze statue of astronaut, Congressman-elect and Denver native Jack Swigert. Swigert, who flew on Apollo 13 as Command Module Pilot, was elected to the House of Representatives in 1982, the statue is dressed in an A7L pressure suit, and is posed holding a gold-plated helmet

8.
Front Range
–
It is the first mountain range encountered moving west along the 40th parallel north across the Great Plains of North America. The Front Range runs north-south between Casper, Wyoming and Pueblo, Colorado and rises nearly 10,000 feet above the Great Plains, Longs Peak, Mount Evans, and Pikes Peak are its most prominent peaks, visible from the Interstate 25 corridor. The area is a destination for mountain biking, hiking, climbing. Millions of years ago the present-day Front Range was home to ancient mountain ranges, deserts, beaches and this urban corridor benefits from the weather-moderating effect of the Front Range mountains, which help block prevailing storms. About 1 billion years ago, the earth was producing massive amounts of rock that would one day amalgamate, drift together and combine. In the Colorado region, this molten rock spewed and cooled, over the next 500 million years, little is known about changes in the sedimentation after the granite was produced. However, at about 500 –300 million years ago, the region began to sink, eroded granite produced sand particles that began to form strata, layers of sediment, in the sinking basin. Sedimentation would continue to place until about 300 million years ago. Around 300 million years ago, the sinking suddenly reversed, over the next 150 million years, during uplift the mountains would continue to erode and cover themselves in their own sediment. Wind, gravity, rainwater, snow, and ice-melt supplied rivers that ultimately carved through the granite mountains, the sediment from these mountains lies in the Fountain Formation today. Red Rocks Amphitheater outside of Denver, Colorado, is set into the Fountain Formation. At 280 million years ago, sea levels were low and present-day Colorado was part of the super-continent Pangaea, sand deserts covered most of the area spreading as dunes seen in the rock record, known today as the Lyons Sandstone. These dunes appear to be cross-bedded and show various fossil footprints,30 million years later, the sediment deposition was still taking place with the introduction of the Lykins Formation. This formation can be best attributed to its layers of muddy limestone. 250 million years ago, the Ancestral Rockies were burying themselves while the shoreline was present during the break-up of Pangaea and this formation began right after Earth’s largest extinction 251 million years ago at the Permian-Triassic Boundary. Ninety percent of the marine life was destroyed and a great deal on land as well. After 100 million years of deposition, a new environment brought rise to a new formation, the Morrison Formation contains some of the best fossils of the Late Jurassic. It is especially known for its tracks and sauropod bones among other dinosaur fossils

9.
Rocky Mountains
–
The Rocky Mountains, commonly known as the Rockies, are a major mountain range in western North America. The Rocky Mountains stretch more than 3,000 miles from the northernmost part of British Columbia, in western Canada, to New Mexico, in the Southwestern United States. Within the North American Cordillera, the Rockies are somewhat distinct from the Pacific Coast Ranges, the Rocky Mountains were initially formed from 80 million to 55 million years ago during the Laramide orogeny, in which a number of plates began to slide underneath the North American plate. The angle of subduction was shallow, resulting in a belt of mountains running down western North America. Since then, further tectonic activity and erosion by glaciers have sculpted the Rockies into dramatic peaks, at the end of the last ice age, humans started to inhabit the mountain range. The first mention of their present name by a European was in the journal of Jacques Legardeur de Saint-Pierre in 1752, the Rocky Mountains are commonly defined as stretching from the Liard River in British Columbia south to the Rio Grande in New Mexico. The United States definition of the Rockies includes the Cabinet and Salish Mountains of Idaho and their counterparts north of the Kootenai River, the Columbia Mountains, are considered a separate system in Canada, lying to the west of the huge Rocky Mountain Trench. This runs the length of British Columbia from its beginnings in the middle Flathead River valley in western Montana to the bank of the Liard River. The Rockies vary in width from 70 to 300 miles, also west of the Rocky Mountain Trench, farther north and facing the Muskwa Range across the trench, are the Stikine Ranges and Omineca Mountains of the Interior Mountains system of British Columbia. A small area east of Prince George, British Columbia on the side of the Trench. In Canada geographers define three main groups of ranges, the Continental Ranges, Hart Ranges and Muskwa Ranges, the Muskwa and Hart Ranges together comprise what is known as the Northern Rockies. The western edge of the Rockies includes ranges such as the Wasatch near Salt Lake City, the Great Basin and Columbia River Plateau separate these sub-ranges from distinct ranges further to the west, most prominent among which are the Sierra Nevada, Cascade Range and Coast Mountains. The Rocky Mountain System within the United States is a United States physiographic region, the Rocky Mountains are notable for containing the highest peaks in central North America. The ranges highest peak is Mount Elbert located in Colorado at 14,440 feet above sea level, Mount Robson in British Columbia, at 12,972 feet, is the highest peak in the Canadian Rockies. The Continental Divide of the Americas is located in the Rocky Mountains, triple Divide Peak in Glacier National Park is so named because water that falls on the mountain reaches not only the Atlantic and Pacific, but Hudson Bay as well. Farther north in Alberta, the Athabasca and other rivers feed the basin of the Mackenzie River, see Rivers of the Rocky Mountains for a list of rivers. Human population is not very dense in the Rocky Mountains, with an average of four people per square kilometer, however, the human population grew rapidly in the Rocky Mountain states between 1950 and 1990. The 40-year statewide increases in range from 35% in Montana to about 150% in Utah

10.
Colorado River
–
The Colorado River is one of the principal rivers of the Southwestern United States and northern Mexico. The 1, 450-mile-long Colorado River drains an expansive, arid watershed that encompasses parts of seven U. S. starting in the central Rocky Mountains in the U. S. After entering Mexico, the Colorado approaches the mostly dry Colorado River Delta at the tip of the Gulf of California between Baja California and Sonora. Known for its dramatic canyons, whitewater rapids, and eleven U. S. National Parks, the Colorados large flow and steep gradient are used for generating hydroelectric power, and its major dams regulate peaking power demands in much of the Intermountain West. Intensive water consumption has dried up the lower 100 miles of the river, beginning with small bands of nomadic hunter-gatherers, Native Americans have inhabited the Colorado River basin for at least 8,000 years. Most native peoples that inhabit the basin today are descended from groups that settled in the region beginning about 1,000 years ago. Europeans first entered the Colorado Basin in the 16th century, when explorers from Spain began mapping and claiming the area, early contact between Europeans and Native Americans was generally limited to the fur trade in the headwaters and sporadic trade interactions along the lower river. After most of the Colorado River basin became part of the U. S. in 1846, several expeditions charted the Colorado in the mid-19th century – one of which, led by John Wesley Powell, was the first to run the rapids of the Grand Canyon. American explorers collected valuable information that would later be used to develop the river for navigation, lesser numbers settled in the upper basin, which was the scene of major gold strikes in the 1860s and 1870s. Large engineering works began around the start of the 20th century, with guidelines established in a series of international. The U. S. federal government was the driving force behind the construction of dams and aqueducts in the river system, although many state. Most of the dams in the river basin were built between 1910 and 1970, the system keystone, Hoover Dam, was completed in 1935. The Colorado is now considered among the most controlled and litigated rivers in the world, as demands for Colorado River water continue to rise, the level of human development and control of the river continues to generate controversy. The Colorado begins at La Poudre Pass in the Southern Rocky Mountains of Colorado, after a short run south, the river turns west below Grand Lake, the largest natural lake in the state. As it flows southwest, it gains strength from many tributaries, as well as larger ones including the Blue, Eagle. In a few areas, such as the marshy Kawuneeche Valley near the headwaters, arcing northwest, the Colorado begins to cut across the eponymous Colorado Plateau, a vast area of high desert centered at the Four Corners of the southwestern United States. In Utah, the Colorado flows primarily through the slickrock country and this is one of the most inaccessible regions of the continental United States. Here, the San Juan River, carrying runoff from the slope of Colorados San Juan Mountains, joins the Colorado from the east. S

11.
Wildlife
–
Wildlife traditionally refers to undomesticated animal species, but has come to include all plants, fungi, and other organisms that grow or live wild in an area without being introduced by humans. Wildlife can be found in all ecosystems, humans have historically tended to separate civilization from wildlife in a number of ways including the legal, social, and moral sense. Some animals, however, have adapted to suburban environments and this includes such animals as domesticated cats, dogs, mice, and gerbils. The global wildlife population has decreased by 52 percent between 1970 and 2014, according to a report by the World Wildlife Fund, anthropologists believe that the Stone Age people and hunter-gatherers relied on wildlife, both plants and animals, for their food. In fact, some species may have been hunted to extinction by human hunters. Today, hunting, fishing, and gathering wildlife is still a significant food source in parts of the world. In other areas, hunting and non-commercial fishing are seen as a sport or recreation. Meat sourced from wildlife that is not traditionally regarded as game is known as bush meat, in November 2008, almost 900 plucked and oven-ready owls and other protected wildlife species were confiscated by the Department of Wildlife and National Parks in Malaysia, according to TRAFFIC. The animals were believed to be bound for China, to be sold in wild meat restaurants, most are listed in CITES which prohibits or restricts such trade.60. Many Amazon species, including peccaries, agoutis, turtles, turtle eggs, anacondas, armadillos, others in these informal markets, such as monkeys and parrots, are destined for the pet trade, often smuggled into the United States. Still other Amazon species are popular ingredients in traditional medicines sold in local markets, the medicinal value of animal parts is based largely on superstition. Many animal species have spiritual significance in different cultures around the world, for example, eagles, hawks and their feathers have great cultural and spiritual value to Native Americans as religious objects. In Hinduism the cow is regarded sacred, muslims conduct sacrifices on Eid-ul-Adha to commemorate the sacrificial spirit of Ibrahim in love of God. Camels, sheep, goats, and cows may be offered as sacrifice during the three days of Eid, many nations have established their tourism sector around their natural wildlife. South Africa has, for example, many opportunities for tourists to see the wildlife in its national parks. In South India the Periar Wildlife Sanctuary, Bandipur National Park and Mudamalai Wildlife Sanctuary are situated around, India is home to many national parks and wildlife sanctuaries showing the diversity of its wildlife, much of its unique fauna, and excels in the range. This subsection focuses on forms of wildlife destruction. Exploitation of wild populations has been a characteristic of man since our exodus from Africa 130,000 –70,000 years ago

12.
Tundra
–
In physical geography, tundra is a type of biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr uplands, there are three types of tundra, Arctic tundra, alpine tundra, and Antarctic tundra. In tundra, the vegetation is composed of shrubs, sedges and grasses, mosses. Scattered trees grow in tundra regions. The ecotone between the tundra and the forest is known as the line or timberline. Arctic tundra occurs in the far Northern Hemisphere, north of the taiga belt, the word tundra usually refers only to the areas where the subsoil is permafrost, or permanently frozen soil. Permafrost tundra includes vast areas of northern Russia and Canada, the polar tundra is home to several peoples who are mostly nomadic reindeer herders, such as the Nganasan and Nenets in the permafrost area. Arctic tundra contains areas of landscape and is frozen for much of the year. The soil there is frozen from 25–90 cm down, and it is impossible for trees to grow, instead, bare and sometimes rocky land can only support low growing plants such as moss, heath, and lichen. There are two seasons, winter and summer, in the polar tundra areas. During the winter it is cold and dark, with the average temperature around −28 °C. However, extreme temperatures on the tundra do not drop as low as those experienced in taiga areas further south. During the summer, temperatures rise somewhat, and the top layer of seasonally-frozen soil melts, the tundra is covered in marshes, lakes, bogs and streams during the warm months. Generally daytime temperatures during the rise to about 12 °C. Arctic tundras are sometimes the subject of conservation programs. In Canada and Russia, many of areas are protected through a national Biodiversity Action Plan. Tundra tends to be windy, with winds often blowing upwards of 50–100 km/h, however, in terms of precipitation, it is desert-like, with only about 15–25 cm falling per year. Although precipitation is light, evaporation is also relatively minimal, there is a natural pattern of accumulation of fuel and wildfire which varies depending on the nature of vegetation and terrain

Albert Bierstadt was commissioned by the Earl of Dunraven to make a painting of the Estes Park and Longs Peak area in 1876 for $15,000. The painting, originally displayed in Dunraven Castle, is now in the collection of the Denver Art Museum.

Deforestation and increased road-building in the Amazon Rainforest are a significant concern because of increased human encroachment upon wild areas, increased resource extraction and further threats to biodiversity.